Active stylus communication with a digitizer

ABSTRACT

A method includes detecting presence of a handheld device in proximity of a touch enabled device and negotiating communication capabilities between the handheld device and a digitizer system of the touch enabled device. At least one of the handheld device and the digitizer system is configured to match a defined communication capability of the other of the at least one of the handheld device and digitizer system. Input from the handheld device is tracked via an electrostatic communication channel between the handheld device and the digitizer system based on the defined communication configuration.

RELATED APPLICATION

This application is a continuation of and claims priority to U.S.application Ser. No. 16/918,576, entitled “ACTIVE STYLUS COMMUNICATIONWITH A DIGITIZER,” filed Jul. 1, 2020, which is a continuation of U.S.application Ser. No. 14/986,767 (now U.S. Pat. No. 10,739,875, issuedAug. 11, 2020), entitled “ACTIVE STYLUS COMMUNICATION WITH A DIGITIZER,”filed Jan. 4, 2016, which claims the benefit of priority under 35 USC §119(e) of U.S. Provisional Patent Application No. 62/099,524 filed onJan. 4, 2015, all the contents of which are incorporated herein byreference in their entirety.

BACKGROUND

Signal emitting styluses, e.g. active styluses are known in the art foruse with a digitizer system. Position detection of the stylus providesinput to a computing device associated with the digitizer system and isinterpreted as user commands. Often, the digitizer system is integratedwith a display screen, e.g. to form a touch screen. Position of thestylus over the screen is correlated with virtual information portrayedon the screen. The signal emitted by the stylus may include informationsuch as pressure applied on the writing tip and stylus identification.The signal is decoded by the digitizer system to obtain the information.

Digitizer systems typically include a matrix of electrode junctionsarranged in rows and columns. Stylus location may be tracked by samplingoutput in both row and column direction. Tracking is based on detectinga signal emitted by a tip of the stylus and picked up by the digitizersensor due to electrostatic coupling established between the tip and aportion of the matrix of electrode junctions. Digitizer systems thattrack signals emitted by the stylus also typically track input providedwith a finger or conductive object. A mutual capacitive sensor is onetype of digitizer sensor for such digitizer systems. Mutual capacitivedetection allows multi-touch operation where multiple fingers, palms orconductive objects are tracked at the same time.

SUMMARY

The disclosure in some embodiments relates to a method for active styluscommunication with a digitizer system of a computing device and may beapplied to active communication of other handheld devices with adigitizer system of a computing device. The method provides fornegotiating capabilities between a stylus and a digitizer system andconfiguring an electrostatic communication channel between them based onthe negotiating. The capability negotiating may help optimizecommunication between a particular stylus and digitizer system pair. Adifferent configuration may be defined for styluses communicating with asame digitizer system or for a same stylus communicating with differentdigitizer systems. A configuration between a stylus and a digitizersystem may be stored in the computing device, in the stylus or inexternal memory, e.g. a cloud memory and may be fetched based onidentifying the stylus, the digitizer system or both.

Unless otherwise defined, all technical and/or scientific terms usedherein have the same meaning as commonly understood by one of ordinaryskill in the art. Although methods and materials similar or equivalentto those described herein can be used in the practice or testing ofembodiments of the disclosure, exemplary methods and/or materials aredescribed below. In case of conflict, the patent specification,including definitions, will control. In addition, the materials,methods, and examples are illustrative only and are not intended to benecessarily limiting.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Some embodiments of the disclosure are herein described, by way ofexample only, with reference to the accompanying drawings. With specificreference now to the drawings in detail, it is stressed that theparticulars shown are by way of example and for purposes of illustrativediscussion of embodiments of the disclosure. In this regard, thedescription taken with the drawings makes apparent to those skilled inthe art how embodiments of the disclosure may be practiced.

In the drawings:

FIG. 1 is a simplified block diagram of an exemplary touch enabledcomputing device in accordance with some embodiments of the presentdisclosure;

FIG. 2 is a schematic diagram of a touch enabled computing devicecommunicating with two different styluses in accordance with someembodiments of the present disclosure;

FIG. 3 is a schematic diagram of a stylus communicating with twodifferent touch enabled computing devices in accordance with someembodiments of the present disclosure; and

FIG. 4 is a simplified flow chart of an exemplary method for pairing ahandheld device with a touch enabled computing device in accordance withsome embodiments of the present disclosure.

DETAILED DESCRIPTION

In exemplary embodiments of the present disclosure, a computing devicethat is touch enabled is configured to identify capabilities of a stylus(or other handheld devices) coming into proximity with the device and toconfigure communication between the stylus and a touch screen of thecomputing device based on the identified capabilities. In some exemplaryembodiments, operation of the touch screen is adapted to accommodatedetected capabilities of the stylus.

Optionally, the computing device instructs the stylus to adjust itsconfiguration to accommodate capabilities of the touch screen.Alternatively or additionally, a stylus is configured to identifycapabilities of a touch screen of a computing device and to adapt itstransmission based on the identified capabilities. Optionally, anegotiating session allows both the stylus and the computing device todeclare capabilities, request information and configure an electrostaticcommunication channel between them. The electrostatic communicationchannel is the channel at which a conductive portion of the stylus thatis in proximity to the digitizer sensor transmits a signal that ispicked up by the touch screen or receives a signal that is transmittedby the computing device to the touch screen.

In some exemplary embodiments, based on input from the computing device,the stylus may be configured to selectively transmit information thatcan be recognized or used by the computing device. Information supportedby the computing device may include for example, stylus identification,authorization associated with the stylus, pressure applied on the stylustip, tilt of the stylus, battery level, output from one or sensors onthe stylus, ink color of the stylus.

In some exemplary embodiments, configuration of the electrostaticcommunication channel may define data structure and timing of a signaltransmitted by the stylus that can be recognized by the touch screen ordata structure and timing of a signal transmitted on the touch screenthat can be recognized by the stylus. Optionally, a stylus may transmitone or more tables (and/or formulas) to the computing device based onwhich the computing device can decode the information.

In some exemplary embodiments, capability identification or negotiationis communicated via the electrostatic communication channel or via anauxiliary channel, e.g. Bluetooth, near field communication (NFC), radiofrequency communication, e.g. using electromagnetic signals and wired(e.g. USB) tethered connection to the computing device.

In exemplary embodiments of the present disclosure, communication ofelectrostatic communication capabilities for pairing the devices occurswhen one of the stylus or the computing device becomes aware of theother, e.g. after a defined period of no communication has lapsed.Awareness may be via the electrostatic communication channel or viaalternate channels, e.g. Bluetooth, near field communication (NFC), andUSB tethered connection to the computing device. Once the communicationis configured, stylus or computing device may periodically transmit acode or to confirm the continued configuration. Optionally, the stylusor computing device may initiate a change in the configuration duringstylus interaction with the computing device. Optionally, pairing occurswhile the stylus is not interacting with the touch screen.

Reference is now made to FIG. 1 showing a simplified block diagram of anexemplary touch enabled computing device in accordance with someembodiments of the present disclosure. According to some embodiments ofthe present disclosure, a computing device 100 includes a display 45that is integrated with a digitizer sensor 50. In some exemplaryembodiments, digitizer sensor 50 is a grid based capacitive sensorformed with row and column conductive strips 58 forming grid lines ofthe grid based sensor. Typically, conductive strips 58 are electricallyinsulated from one another and each of conductive strips is connected atleast at on one end to digitizer circuitry 25.

Typically, conductive strips 58 are arranged to enhance capacitivecoupling between row and column conductive strips, e.g. around junctions59 formed between rows and columns. The capacitive coupling formedbetween the row and column conductive strips is sensitive to presence ofconductive and dielectric objects. Alternatively, digitizer sensorformed with a matrix of electrode junctions that is not necessarilyconstructed based on row and column conductive strips.

According to some embodiments of the present disclosure, conductivestrips 58 are operative to detect touch of one or more fingertips 140 orhand 142 or other conductive objects as well as input by stylus 120transmitting an electromagnetic signal typically via the writing tip ofthe stylus. Digitizer circuitry 25 applies mutual capacitance detectionor a self-capacitance for sensing a touch signal from touch (or hover)of fingertip 140. Typically, during mutual capacitance andself-capacitance detection, digitizer circuitry 25 sends a triggeringsignal, e.g. pulse to one or more conductive strips 58 of digitizersensor 50 and samples output from conductive strips 58 in response tothe triggering and/or interrogation. In some embodiments, some or all ofconductive strips 58 along one axis of the grid are triggeredsimultaneously or in a consecutive manner, and in response to eachtriggering, outputs from conductive strips 58 on the other axis aresampled. Typically, this procedure provides for detecting coordinates ofmultiple fingertips 140 touching sensor 50 at the same time(multi-touch).

Digitizer circuitry 25 typically includes finger detection engine 26 formanaging the triggering signal, for processing the touch signal and fortracking coordinates of one or more fingertips 140. Digitizer circuitry25 also typically includes stylus detection engine 27 for synchronizingwith stylus 120, for processing input received by stylus 120 and/or fortracking coordinates of stylus 120. Typically, output from both row andcolumn conductive strips 58, e.g. from two perpendicular axes aresampled to detect coordinates of stylus 120.

Input received by stylus 120 may include information directly related tostylus 120, related to an environment around the stylus 120, to a userusing stylus 120, to privileges allotted to the stylus 120, capabilitiesof stylus 120, or information received from a third party device.Information related to the stylus may include indications of a pressedbutton(s) 35, pressure level on tip 20, tilt, identification,manufacturer, version, media access control (MAC) address, and storedconfigurations such as color, tip type, brush, and add-ons.

Typically, stylus 120 includes an ASIC 40 that controls generation of asignal emitted by stylus 120. ASIC 40 typically encodes informationgenerated, stored or sensed by stylus 120 on the signal transmitted bystylus 120. Typically, stylus detection engine 27 decodes informationreceived from stylus 120. Optionally, other handheld devices configuredto interact with digitizer sensor 50 may be operated in a similar mannerand tracked by stylus detection engine 27.

Typically, output from digitizer circuitry 25 is reported to host 22.Typically, the output provided by digitizer circuitry 25 may includecoordinates of one or more fingertips 140, coordinates of writing tip 20of stylus 120 and additional information provided by stylus 120, e.g.pressure, tilt, and battery level. Typically, digitizer circuitry 25uses both analog and digital processing to process signals detected withdigitizer sensor 50. Optionally, some and/or all of the functionalitiesof engines 26 and 27 are integrated in one or more processing unitsadapted for controlling operation of digitizer sensor 50.

Optionally, some and/or all of the functionalities of digitizercircuitry 25, engines 26 and 27 are integrated and/or included in host22. Host 22 may transmit the information to an application manager or arelevant application. Optionally, circuit 25 and host 22 may transferthe raw information to an application. The raw information may beanalyzed or used as needed by the application. At least one of stylus120, circuit 25 and host 22 may pass on the raw information withoutanalysis or being aware of the information.

According to some exemplary embodiments, stylus 120 additionallyincludes a wireless communication unit 30, e.g. an auxiliary channelwith Bluetooth communication, near field communication (NFC), radiofrequency (RF) communication using module 23 of host 22. In someexemplary embodiments, pairing between stylus 120 and computing device100 to define a communication configuration for the electrostaticcommunication channel is negotiated via the auxiliary channel.Alternatively, negotiation may be via tip 20 of stylus 120 that picks upan up-link signal transmitted via conductive strips 58 or a dedicatedconductive strip that is not used for position tracking.

In some exemplary embodiments, host 22 or circuit 25 instructs stylus120 to update or configure its transmission protocol based on analysisand reports from circuit 25 and host 22. Alternatively or additionally,stylus 120 may instruct host 22 or circuit 25 to configure its samplingand processing protocol based to accommodate input from stylus 120.

A communication configuration negotiated between a stylus 120 andcomputing device 100 may be stored in memory 200. Memory 200 may belocal memory integrated in computing device 100 or stylus 120 or may beremote memory included in a network computer or in a cloud memory. Insome exemplary embodiments, the communication configuration once definedmay be fetched whenever computing device 100 and stylus 120 based on anidentification code that identifies the desired configuration.

Reference is now made to FIG. 2 showing a schematic diagram of a touchenabled computing device communicating with two different styluses inaccordance with some embodiments of the present disclosure. According tosome embodiments of the present disclosure, styluses 121 and 123 havingdifferent capabilities or defined operation schemes may be detected by asame touch enabled computing device 100. Optionally, differentconfiguration may be defined for communicating with each of stylus 121and 123. For example, stylus 121 may transmit a signal 151 based on oneconfiguration and stylus 123 may transmit a signal 151 based on anotherconfiguration and computing device 100 may adapt itself to receive bothsignal 151 and signal 153. Inputs from styluses 121 and 123 may besimultaneous or consecutive.

Optionally, computing device 100 may also transmit signals to styluses121 and 123 via digitizer sensor 50. Optionally, the configuration fortransmitting signals to each of stylus 121 and stylus 123 is alsodifferent. For example, computing device 100 may transmit a firstsynchronization signal to stylus 121 and another synchronization signalto stylus 123. A configuration between a stylus 121 and computing device100 as well as configuration between stylus 123 and computing device 100may be stored in memory 200.

The different communication configurations may be defined based on thecapabilities of the different styluses. Optionally, the communicationconfiguration may be defined based on needs of an application running oncomputing device 100 and receiving input from a particular stylus. Inone exemplary embodiment, stylus 121 may be a high-end stylus that canreport more information as compared to a low-end stylus, e.g. stylus123.

Optionally, stylus 121 can report pressure data with a high resolution,report tilt information and is capable of transmitting with higherrepeat rate. Stylus 123, on the other hand may only reports pen up orpen down and may transmit at a relatively now repeat rate. Computingdevice 100 may agree to configure signal 151 to accommodate thecapabilities of stylus 121 and configure communication channel 153 toaccommodate stylus 123. Alternatively, computing device 100 may requestthat stylus 121 configure signal 151 to be similar to signal 153.Configuring a communication channel may include defining informationtransmitted, a frequency for transmission, frame timing, symbol size,symbol timing, signal modulation, baud rate and coding.

Reference is now made to FIG. 3 showing a schematic diagram of a styluscommunicating with two different touch enabled computing devices inaccordance with some embodiments of the present disclosure. In someexemplary embodiments, a same stylus 121 may communicate with one touchenabled computing device 101 using a first configuration and maycommunicate with another touch enabled computing device 102 usinganother configuration. Pairing between stylus 121 and each of computingdevice 101 and computing device 102 may be stored in memory 200. Forexample, stylus 121 may be configured to transmit signal 151 includingpressure information to computing device 101 and may be configured totransmit another signal 152 including tilt information to a computingdevice 102. Optionally, stylus 121 is configured to transmit at a firstfrequency when communicating with device 101 and to transmit at anotherfrequency when communicating with device 102.

Reference is now made to FIG. 4 showing a simplified flow chart of anexemplary method for pairing a handheld device with a touch enabledcomputing device in accordance with some embodiments of the presentdisclosure. According to exemplary embodiments of the presentdisclosure, pairing between a handheld device, e.g. a stylus and acomputing device is initiated when the computing device becomes aware ofthe handheld device (block 410).

Optionally, awareness occurs as the handheld device approaches thecomputing device and communication between the handheld device and thecomputing device is established. In some exemplary embodiments,communication established via the electrostatic channel initiatespairing, e.g. responsive to the computing device detecting a beaconsignal transmitted by the stylus. Optionally, pairing is initiated whenthe handheld device is detected on the digitizer sensor. Alternatively,pairing is initiated responsive to the handheld device establishingcommunication with the computing device via Bluetooth, near fieldcommunication (NFC), radio frequency communication, e.g. usingelectromagnetic signals and USB tethered connection.

Once awareness occurs, handheld device and computing device maynegotiate capabilities via a selected communication channel (block 415).Typically, the selected communication is other than electrostaticcommunication channel. Negotiation may include transmitting informationfrom the handheld device to the computing device, from the computingdevice to the handheld device or both.

In some exemplary embodiments, the handheld device communicatesidentification data to the computing device and the computing devicederives the capabilities of the stylus based on the identification data.Identification data may include MAC address, manufacturer information,version, e.g. original design manufacturer (ODM) versions, firmware (FW)version, and software upgrade. In some exemplary embodiments, thehandheld device communicates the type of information that is stored orprovided by the handheld device e.g. operating color, tip type, add-ons,button setting. Add-ons may include tilt information, e.g. from agyroscope embedded in the handheld device. In response, the computingdevice may adapt the digitizer system to the reported capabilities ormay transmit a request to the handheld device to adjust operatingparameters. Alternatively, the computing device may transmitcommunication capabilities to the handheld device and the handhelddevice may adapt itself to the reported capabilities.

Based on negotiation, an electrostatic communication channel fortracking position of the handheld device and information is configured(block 420). Typically, the configuration defines the information thatwill be provided by the handheld device. Optionally, one or more offrequency, frame timing, symbol size, modulation, symbol timing, baudrate and coding is configured based on the negotiation. Optionally,during the negotiation one or more look-up tables for interpretingtransmission information is provided by the handheld device, and thecomputing device stores and uses the look-up tables.

Optionally, the established configuration is stored and can be fetchedbased on an identification code that identifies the desiredconfiguration. The configuration may be stored locally, e.g. in thestylus ASIC or in the computing device or may be stored remotely, e.g.in a network memory or a cloud memory and can be accessed remotely.

The digitizer system integrated in the computing device typically tracksinput from the handheld device as long as communication between thehandheld device and the computing device is maintained (block 425) Insome exemplary embodiments, one or more of the handheld device and thecomputing device continues to transmit the configuration code thatidentifies the defined working configuration. Alternatively orperiodically, one or more of the handheld device and the computingdevice continues to transmit pairing information to the other duringtracking. In some exemplary embodiments, the pairing information istransmitted while the handheld device is hovering as opposed to touchingthe touch screen of the computing device.

In some exemplary embodiments, once the electrostatic communicationchannel is broken, e.g. signal from handheld device is lost pairing isreinstated (block 430) Optionally, pairing is only initiated after apre-defined time period that electrostatic communication is broken, e.g.1-3 seconds. In some exemplary embodiments, paring may be reinstatedbased on the handheld device transmitting and the computing deviceconfirming the configuration code previously defined. Alternatively,pairing may be reinstated based on the computing device transmitting andthe handheld device confirming the configuration code previouslydefined.

In some exemplary embodiments, the computing device communicates withthe handheld device in a basic level prior to (or during) capabilitynegotiation and then adapts the communication configuration as requiredbased on the negotiation. Capability negotiation may occur over one ormore frames. The information may be set as a single package or asmulti-sub messages that might be sequential or divided by other higherpriority data. Each sub-message may have a package number so that thepackage may be rebuilt.

The handheld device may dynamically request a change in theconfiguration to save power. Optionally, parameters such as transmissionlevel, frequency, baud rate may be adjusted based on a power level ofthe battery in the handheld device. Optionally, a change in theconfiguration may be initiated due to a detected SNR ration. Optionally,the configuration may be adjusted to improve SNR.

According to some exemplary embodiments, there is provided a methodcomprising: detecting presence of a handheld device in proximity of atouch enabled device; negotiating communication capabilities between thehandheld device and a digitizer system of the touch enabled device;configuring at least one of the handheld device and the digitizer systemto match a defined communication capability of the other of the at leastone of the handheld device and digitizer system; and tracking input fromthe handheld device via an electrostatic communication channel betweenthe handheld device and the digitizer system based on the definedcommunication configuration.

Optionally, the negotiating communication capabilities is performed viaa communication channel other than the electrostatic communicationchannel.

Optionally, the negotiating communication capabilities is repeatedperiodically while communication via the electrostatic communicationchannel is sustained.

Optionally, the negotiating communication capabilities is repeated aftera lapse in communication via the electrostatic communication channel.

Optionally, the detecting presence of a handheld device in proximity ofthe touch enabled device is based on input detect by the digitizersystem.

Optionally, the communication capability includes at least one offrequency for transmission, frame timing, symbol size, symbol timing,signal modulation, baud rate and coding.

Optionally, the communication capability includes communicating supportof reception of data related to information sensed or stored in thehandheld device.

Optionally, the method includes defining a first communicationconfiguration between a first handheld device and the digitizer sensorand defining a second communication configuration between a secondhandheld device and the digitizer sensor.

Optionally, the method includes defining a first communicationconfiguration between the handheld device and a first digitizer sensorand defining a second communication configuration between the handhelddevice and a second digitizer sensor.

Optionally, the handheld device transmits identification information tothe touch enabled computing device and wherein the computing devicedetermines the communication capabilities of the handheld device basedon the identification information.

Optionally, the negotiating communication capabilities is performed overa plurality of transmission cycles between the handheld device and thedigitizer sensor.

Optionally, the input from the handheld device is tracked via theelectrostatic communication channel using a first basic communicationconfiguration prior to the configuring.

Optionally, information encoded in the input is decoded based on thedefined configuration.

Optionally, the configuring includes selecting information to beprovided to the touch enabled computing device by the handheld device.

Optionally, the method includes storing the defined communicationconfiguration is association with an identification code; andconfiguring the at least one of the handheld device and the digitizersystem based on detecting the identification information.

According to some exemplary embodiments, there is provided systemcomprising: a touch enabled computing device configured to detect asignal from a handheld device via an electrostatic communication channelprovided by a digitizer sensor integrated on the computing device; thehandheld device comprising: a circuit configured to generate the signal;and a conductive electrode from which the signal is transmitted; andwherein the handheld device and the computing device are configured tonegotiate communication capabilities for the electrostatic communicationchannel and wherein at least one of the handheld device and thedigitizer system is configured to match a defined communicationcapability of the other of the at least one of the handheld device anddigitizer system based on the negotiating.

Optionally, the conductive electrode is a conductive tip.

Optionally, the device includes a second communication channel betweenthe touch enabled computing device and the handheld device that is otherthan electrostatic communication channel, wherein negotiatingcommunication capabilities occurs via the second communication channel.

Optionally, negotiating communication capabilities is repeatedperiodically while communication via the electrostatic communicationchannel is sustained.

Optionally, negotiating communication capabilities is repeated after alapse in communication via the electrostatic communication channel.

According to some exemplary embodiments, there is provided systemcomprising a conductive tip from which the signals are transmitted orreceived; and a circuit in communication with the conductive tip, thecircuit configured to:

generate and process signals; and negotiate communication capabilitiesfor an electrostatic communication channel to match a definedcommunication capability of another device.

Optionally, the circuit is further configured to negotiate communicationcapabilities repeatedly based on a specified period while communicationvia the electrostatic communication channel is sustained.

Certain features of the examples described herein, which are, forclarity, described in the context of separate embodiments, may also beprovided in combination in a single embodiment. Conversely, variousfeatures of the examples described herein, which are, for brevity,described in the context of a single embodiment, may also be providedseparately or in any suitable sub-combination or as suitable in anyother described embodiment of the disclosure. Certain features describedin the context of various embodiments are not to be considered essentialfeatures of those embodiments, unless the embodiment is inoperativewithout those elements.

What is claimed is:
 1. A method comprising: detecting presence of atleast two styli in proximity of a touch-enabled device comprising adigitizer; negotiating separate communication capabilities between theat least two styli and a digitizer system of the touch-enabled device;transmitting a first synchronization signal to a first stylus, the firstsynchronization signal defined based on first capabilities of the firststylus; transmitting a second synchronization signal to a second stylus,the second synchronization signal defined based, at least in part, onsecond capabilities of the second stylus that differ from the firstcapabilities of the first stylus; tracking input from the first stylus;and configuring the digitizer system to communicate with both the firststylus and the second stylus in accordance with the firstsynchronization signal and the second synchronization signal,respectively.
 2. The method of claim 1, further comprising detecting, bythe touch-enabled device, the capabilities of the first stylus and thecapabilities of the second stylus.
 3. The method of claim 1, furthercomprising: wherein said detection of the first stylus comprisesdetecting the first stylus in proximity to the touch-enabled device viaa first electrostatic communication channel; and incident to saiddetection, initiating pairing between the first stylus and thetouch-enabled device.
 4. The method of claim 3, further comprising:wherein said detection of the second stylus comprises detecting thesecond stylus in proximity to the touch-enabled device via the first ora second electrostatic communication channel; and incident to saidadditional detection, initiating pairing between the second stylus andthe touch-enabled device.
 5. The method of claim 1, wherein the firstsynchronization signal comprises a first pre-defined configuration. 6.The method of claim 1, wherein the first synchronization signalcomprises at least one member of a group comprising symbol size,modulation, symbol timing, or baud rate.
 7. The method of claim 1,wherein said negotiating separate communication capabilities involvesinitiating negotiating sessions with the at least two styli that allowat least one of the at least two styli or the touch-enabled device todeclare capabilities.
 8. The method of claim 1, wherein the first stylustransmits identification information to the touch-enabled device andwherein the touch-enabled device determines the first synchronizationsignal based on the identification information.
 9. The method of claim1, wherein the second stylus transmits identification information to thetouch-enabled device and wherein the touch-enabled device determines thesecond synchronization signal based on the identification information.10. The method of claim 1, wherein said negotiating of separatecommunication capabilities is performed over a plurality of transmissioncycles between the first or second stylus and the digitizer system. 11.A method comprising: detecting presence of at least two styli inproximity to a touch-enabled device configured to execute anapplication; negotiating separate communication capabilities between theat least two styli and a digitizer system of the touch-enabled device;transmitting a first synchronization signal to a first stylus, the firstsynchronization signal defined based on a first need of the application;transmitting a second synchronization signal to a second stylus, thesecond synchronization signal defined based on a second need of theapplication that differs from the first need; tracking input from thefirst stylus; and configuring the digitizer system to communicate withboth the first stylus and the second stylus in accordance with the firstsynchronization signal and the second synchronization signal,respectively.
 12. The method of claim 11, further comprising: whereinsaid detection of the first stylus comprises detecting the first stylusin proximity to the touch-enabled device via a first electrostaticcommunication channel; and incident to said detection, initiatingpairing between the first stylus and the touch-enabled device.
 13. Themethod of claim 12, further comprising: wherein said detection of thesecond stylus comprises detecting the second stylus in proximity to thetouch-enabled device via the first or a second electrostaticcommunication channel; and incident to said additional detection,initiating pairing between the second stylus and the touch-enableddevice.
 14. The method of claim 11, wherein the first synchronizationsignal comprises a first pre-defined configuration.
 15. The method ofclaim 11, wherein the first synchronization signal comprises at leastone member of a group comprising symbol size, modulation, symbol timing,or baud rate.
 16. A system, comprising: a touch-enabled deviceconfigured to detect signal from at least two styli via one or moreelectrostatic communication channels provided by a digitizer systemintegrated on the touch-enabled device, wherein the touch-enabled deviceis configured to: negotiate separate communication capabilities betweenthe at least two styli and a digitizer system of the touch-enableddevice, transmit a first synchronization signal to a first stylus,transmit a second synchronization signal to a second stylus, trackinginput from the first stylus, and configuring the digitizer system tocommunicate with both the first stylus and the second stylus inaccordance with the first synchronization signal and the secondsynchronization signal, respectively.
 17. The system of claim 16,wherein the first synchronization signal is defined based on eitherfirst capabilities of the first stylus or a first need of an applicationrunning on the touch-enabled device.
 18. The system of claim 16, whereinthe second synchronization signal is defined based on either secondcapabilities of the second stylus or a second need of an applicationrunning on the touch-enabled device.
 19. The system of claim 16, whereinthe first stylus comprises a circuit configured to generate the firstsynchronization signal and a conductive electrode from which the firstsynchronization signal is transmitted.
 20. The system of claim 16,wherein the touch-enabled device is further configured to detect batterylevels of the first stylus and the second stylus.